Mature DS games are pretty uncommon considering the target audience of the system. Mature rated games are almost unheard of, but Theresia tries to change that with a creepy, bloody, violent take on the Shadowgate-style graphic adventure. While the survival horror genre has yet to reach its potential, Theresia does little to remedy. Despite a strong storyline, Theresia offers a mediocre and unpolished experience overall.

Theresia contains two separate but related stories, the second only playable after completing the first. The first story, "Dear Emile," puts the player in control of an amnesiac girl lost in a spooky mansion without a hint as to the reasoning behind her isolation. She attempts to gather her memories and uncover the truth behind her preoccupation with blood. "Dear Martel," the second story, involves a similar situation: bereft of memory, a man awakens in a dismal room and must search the decaying halls of a mansion to recover his lost memories.

Dear Emile features an excellent story that explores the themes of obsessive and possessive relationships, loss, guilt, and the unique mother-daughter bond. Despite the hackneyed amnesia theme, the story manages to stray from most other clichés. The story unfolds as the main character uncovers pages from journals pertaining to her past. These trigger blatantly enigmatic memory sequences shown in still illustrations and detached dialogue. At the outset, these may be a source of irritation due to their apparent lack of coherence and arguably ugly artwork. Eventually, however, the memories coalesce into something profoundly disturbing yet oddly touching.

Dear Martel features a weaker story with less developed relationships and themes; two elements that made the first one so engaging. Even still, it builds on the Theresia lore and enhances the first story as well as presenting some interesting concepts of its own. As with the first story, Dear Martel unfolds through a series of journal entries, which trigger less meaningful memories than those found in Dear Emile. Taken together, however, the two stories tell a tragic tale of the polar aspects of many close relationships: comfort and pain.

Unfortunately, the writing is only painful. Despite crediting two proofreaders, Theresia's script is riddled with errors, including grammatical, spelling, and typographical mistakes. Every fifth line of text contains some type of error, be it a tense issue, missing letters, or misspelled words. There was even at least one room with the incorrect description. This rarely interfered with the gameplay or the understanding of the story, but this sort of sloppiness is inexcusable. Evidently no one informed WorkJam that proofreaders actually need to be familiar with the English language. Here's a hint: "loose" is an entirely different word from "lose."

Unlike the story, Theresia's gameplay offers few surprises, and those that are present are more frustrating than anything else. Unlike most graphic adventures, Theresia is broken up into two types of exploration. While exploring mansion corridors, the game adopts a first person dungeon crawler setup, with bland and repetitive 3D hallways and obstacles. When the player stumbles upon an interesting feature, a generic icon appears, allowing the player to switch to a 2D point-and-click style of exploration. Most of the game's rooms are presented in this style, and that's a mercy.

Navigating the corridors in first person quickly becomes a chore. The mansion in the first story is massive, and there are plenty of poorly textured hallways for the player to explore, but thanks to the in-game map, getting lost isn't the problem. Whether using the stylus or the D-pad, walking and turning speeds are painfully slow, and backtracking is a nightmare as a result. Fortunately, the size of the mansion in the second story is much more limited. While this approach to exploration makes the locations seem more realistically large, it ends up just feeling archaic.

The point-and-click portions of Theresia are generally better, with sufficiently dingy and creepy artwork that sets an oppressive atmosphere. There are plenty of objects to examine, pick up, and use, although the interface is once again cumbersome. To aggravate the situation, the developers included a life bar, which predictably prompts a "Game Over" should it run down. This seems perfectly fine and realistic until the player uncovers the dozens of traps set up throughout both portions of the game. Just opening the wrong desk drawer or thumbing through the incorrect book can cause an arrow to shoot out, draining the life bar. While the traps make sense most of the time (less so in the second story), they feel contrived at times and no less annoying.

The puzzles are obviously a major draw to a game like Theresia, and in that respect, the game barely reaches mediocrity. Most of Theresia's puzzles involve finding item X to surpass obstacle Y to obtain key Z and enter the respective room in order to repeat the cycle endlessly. Creativity is rare here, and several puzzles require obscure or illogical solutions that will have many players heading to a walkthrough. Worst of all, Theresia isn't a game one wants to get stumped during, especially during the first story. Thanks to dreadful navigation and the scope of the game's locations, knowing that the matchstick you need to continue could be anywhere in the enormous, convoluted mansion is the most terrifying scenario in the game.

Thankfully, Theresia makes a few small efforts to maintain playability. The most effective of those is a hint item. When used, this item gives players tips on what to do next. All too often, the information supplied by the item is insultingly obvious. In front of a door with a lock, the "hint" might report that the door is locked and needs a key; truly a revelation. This item's most useful aspect informs the player if anything important is left in a room. If used in every room, getting stumped can almost always be avoided.

Theresia also offers excellent summaries of the stories once the games are completed. Players are allowed to view the characters' memories in chronological order for the first time, with added exposition to clear up most confusion. Finally, the atmosphere of the mansions makes the game more tolerable. At times, Theresia's environments approach those of Silent Hill in their sheer ability to unnerve. Ominous ambient music and eerie melody-driven tracks are used effectively as well, even if they're not all memorable.

After fifteen to twenty hours, most players will finish Theresia and forget about their vexations with the gameplay and the unremarkable puzzles, but they will not forget the stories told. Theresia contains an above average tale marred by incompetent copy-editing and an aged interface. Had the entirety of Theresia been as carefully crafted as its stories, the game may have eked out a subgenre of its own. As it is, however, there will be too few gamers who dare to wipe the dust off this unpolished mess to uncover the value within. Much like its protagonists' memories, Theresia will be lost in a place no one dares enter: that spooky drawer reserved for the video games no one wants to play.